I am wondering how this are was built? Is this a custom app or something using pages or does this "Providers" app exist somewhere? I need something very very similar and wondering if it's custom,

This is a simple pages database with a customized listing and display template 

 

This is a simple pages database with a customized listing and display template 

Thanks for you reply. Is this how the reviews work as well? 

 

Thanks for you reply. Is this how the reviews work as well? 

Yes, page records can have comments and reviews out of the box.